Python读取环境变量的方法和自定义类分享

使用os.environ来读取和修改环境变量：

import os
print (os.environ["TEMP"])
mydir = "c:\\mydir"

os.environ["MYDIR"] = mydir

print (os.environ["MYDIR"])
pathV = os.environ["PATH"]

print (pathV)

os.environ["PATH"]= mydir + ";" + os.environ["PATH"]

print (os.environ["PATH"])

自定义的python的环境变量类：

import os
class MyEnv:
  def __init__(self):

    self.envFile = "c:\\myenv.txt"

    self.envs = {}

  

  def SetEnvFile(self, filename) : 

    self.envFile = filename

        

  def Save(self) :

    outf = open(self.envFile, "w")

    if not outf:

      print ("env file cannot be opened for write!")

    for k, v in self.envs.items() :

      outf.write(k + "=" + v + "\n")

    outf.close()

    

  def Load(self) :

    inf = open(self.envFile, "r")

    if not inf:

      print ("env file cannot be opened for open!")

    for line in inf.readlines() :

      k, v = line.split("=")

      self.envs[k] = v

    inf.close()

    

  def ClearAll(self) :

    self.envs.clear()

    

  def AddEnv(self, k, v) :

    self.envs[k] = v

    

  def RemoveEnv(self, k) :

    del self.envs[k]

    

  def PrintAll(self) :

    for k, v in self.envs.items():

      print ( k + "=" + v )

   

if __name__ == "__main__" :

  myEnv = MyEnv()

  myEnv.SetEnvFile("c:\\myenv.txt")

  myEnv.Load()

  myEnv.AddEnv("MYDIR", "c:\\mydir")

  myEnv.AddEnv("MYDIR2", "c:\\mydir2")

  myEnv.AddEnv("MYDIR3", "c:\\mydir3")

  myEnv.Save()

  myEnv.PrintAll()